Combustion apparatus



y 1965 w. a. SWARTZ ETAL 3,195,607

- comsus'rxon arrm'rus Filed May 5, 1964 2 Sheets-Sheet l lNVE/VWRS. WILLIAM G. SWARTZ WILL/AM R SWARTZ ATTORNEY y 20, 1965 w. s. SWARTZ ETAL 3,

COMBUSTION APPARATUS Filed May 5, 1984 2 Sheets-Sheet 2 INVENTO/PS- WILLIAM G. SWARTZ WILL/AM I. .S'WA/PTZ ATTORNEY SVgWQ United States Patent 0 3,195,6ii7 CGMBUSHUN APPARATUS William G. Swartz, North Hills, and William F. gvvartz, Willow Grove, Pa. (both of Box 543, North Hills,

lenside, Pa.)

Fiied May 5, 19M, Ser. No. 365,676 15 Claims. (Cl. 158-4) This is a continuation-in-part of application Serial No. 275,951, filed Apr. 26, 1963, now abandoned.

This invention relates to combustion apparatus and more particularly to combustion apparatus for burning oil with a blue flame.

Blue flame combustion is known to be chemically different from the common red or yellow flame combustion.

The chain type carbon molecule is propagated Whenever open or natural combustion takes place. Chemically it is identified by an almost instant transition from th hydrocarbon fuel, thru a low quality CO, to CO One characteristic of red flame combustion is the noise produced by this rapid chemical reaction, ranging from the sound of a bonfire to the roar of .a blow torch or a jet engine. Another characteristic of red flame combustion is the production of smoke or free carbon depending upon the volatility of the fuel and/or the temperature of the flame.

As related to the operation of domestic heating oil burners, red flame combustion will become less adequate as the oil refineries continue to produce heavier and less volatile fuels for this market.

The ring type aldehydrous molecule is propagated from a hydro carbon fuel only where the environment is conducive to (l) the complete vaporization of the fuel, (2) a process for delaying the formation of the CO molecule, and (3) a system for limiting or controlling the generation of radiant heat at the zone of CO generation.

Then when a high quality CO gas is thus generated, its burn-ott as CO by the percolation of air thru the rising CO is academic.

It has been common practice with the arrangements of oil fired burners and combustion chambers heretofore proposed to effect the burning of the oil with a red flame. The production of such a flame requires a maximum of turbulence, such flame attains its best efiiciency at high temperature and combustion takes place very quickly. Combustion with a red flame also requires a ceramic refractory lined combustion chamber with radiant heat feed back to the zone of flame propagation. Careful adjustment of air supplies to the particular fuel is also necessary to avoid soot deposits on cool surfaces and to avoid smoke generation. This soot deposit or carbon precipitation has recently been more evident due to the blending of increased amounts of catalytic cracked oil with the ideal straight run #2 oil, by most refineries. And where, in some localities, only 100% catalytic cracked oil is available, the only recourse has been to boost the atomizing pressure and clean the heaters two or three times a season. The difliculties of burning such oil with a blue flame in previously available equipment are great if not impossible.

The signal quality of blue flame combustion is its stability. In contrast to red flame combustion, it is eminently clean and eflicient. When the hydrocarbon fuel is thus processed or converted into the ring type blue flame molecule, there cannot be any precipitation of carbon, smoke or soot on any of the heater surfaces; absorption of the heat latent in the blue flame by surrounding media is more rapid; no sound of combustion is audible; the temperature of combustion is at a level (1100 F.) as to render ordinary'materials of construction, indestructible; combustion at such low non-incandescent temperatures is proof against puffs, i.e., un-

Patented July 2Q, 1%65 ice scheduled ignition of vapors from incandescent refractory surfaces; the possibility of dilution, or excess air, is necessarily design controlled to secure a high chemical eificiency (high CO and there is provided the required time delay to resolve the olefinic hydrocarbons found in catalytic fuels, thus eliminating these characteristic odors of oil combustion. The blue flame, with its shorter wav length, has a better penetration through metal, water and air and provides a more effective heat exchange. The greater volume also increases the eifectiveness of heat transfer in the secondary heating passages in the boiler which are not directly exposed to the combustion space. No ceramic refractory lining is necessary or desirable, so that the hazards of ignition from incandescent ceramic refractory surfaces is avoided.

It is the principal object of the present invention to provide improved combustion apparatus for the combustion of oil in a plurality of stages, first with carbon monoxide production and then with completion with a blue flame.

It is a further object of the present invention to provide combustion apparatus for burning of oil with a blue flame with increased stability and efliciency, with a clean smoke free and soot free operation, with the combustion effected quietly, and with increased effectiveness of the heat exchange to the medium to be heated.

it is a further object of the present invention to provide combustion apparatus for the burning of oil for heat output in boilers and the like which can be made in a form especially adapted for quick and easy assembly for use.

It is a further object of the present invention to provide combustion apparatus for the burning of oil for heating in which the components are simple in construction, easily assembled and adjustable as desired.

It is a further object of the present invention to provide combustion apparatus for burning oil with a blue flame which accommodates differences in the heat absorption rate, the diflerences in the skin temperatures encountered in steam and Water boilers and warm air furnaces, and the ditferences in refinery product in various parts of the country. 7

It is a further object of the present invention to provide combustion apparatus for burning oil with a blue flame which employs a bifurcated target with a cooled surface disposed to provide the time and travel delay required.

It is a further object of the present invention to provide combustion apparatus for burning oil with a blue flame having a first section for carbon monoxide generation and partial completion of combustion and a burnoff section thereabove. 7

It is a further object of the present invention to provide combustion apparatus for burning oil with a blue flame having a jet assembly disposed with respect to the fuel atomizing nozzle and nozzle body such that a controlled flow of heat is provided to the .fuel in the nozzle body to maintain the desired elevated fuel temperature in the nozzle.

Other objects and advantageous features of the invention will be apparent from the description and claims.

The nature and characteristic features of the invention will be more readily understood from the following description taken in connection with the accompanying drawings forming part thereof, in which:

FIGURE 1 is a side elevational view of a combustion apparatus in accordance with the invention in position in a heating boiler;

FIG. 2 is a top plan view, enlarged, of the combustion apparatus shown in FIG. l;

H6. '2 is a top plan view, enlarged, of the combustion approximately on the line 3-3 of FIG. 2;

holds these parts together.

FIG. 4 is a vertical transverse sectional view taken approximately on the line 4-4 of FIG. 3; 7

FIG. 5 is a vertical transverse sectional view taken approximately on the line 5-5 of FIG. 3;

FIG. 6 is a horizontal transverse sectionalview taken approximately on the line 66 of FIG. 3; and

FIG. 7 is an enlarged perspective view of the nozzle and nozzle carrier. h

It should, of course, be understood that the description and drawings herein are illustrative merely, and that various modifications and changes can be made in the structure disclosed without departing from the spirit of the invention.

Like numerals refer eral views.

Referring now more air tube 10 is shown. The tube 10 is of well known type having a blower or fan 11, connected thereto for supplying air for combustion but is of a length to locate the structure supported thereby, and hereinafter described, within the boiler or furnace in spaced relation thereto. The air tube 10 extends through the front wall 12 of a to like parts throughout the sev- .boiler or' furnace 14 and is preferably disposed in sealed relation to the wall 12 to prevent air or gas leakage. The furnace .14 is preferably substantially free from air leakage inwardly or gas leakage outwardly and is connected to a conventional flue pipe (not shown). The furnace 14 does not have any ceramic refractory or other similarly lined combustion space therein which would become incandescent. I

The air tube 10 supports and positions an air supply assembly 15, a housing 16 with a target 17, a target support 18, and a burnoif assembly 19 to be described in detail. H

The air supply assembly includes an air box 99 hav- I ing an inner wall 91', an outer wall 92 to which the side margins of the inner wall 91 extend and with openings 93 for delivery of air thereinto through a mounting ring 89, secured to the wall 92, and a bottom wall 95. A bolt or pin 89a extending through the ring 89 and the tube In clined tubular conduit 96 with an inner tapered end 97 to serve as a stop extends through the interiorfrom the outer wall 92 to the inner wall 91 for the reception of a nozzle I body 23; The nozzle body 23 has an oil supply pipe 49 connected thereto for the supply of oil under pressure. The nozzle body23 can be retained in position as determined by the end 97 by spring arm 24 carried by the wall 91. The nozzle body 23 at the inner or front end thereof has a nozzle 26 preferably for delivering a spray of oil in solid or hollow cone form within an angle of and advantageously at an angle of 30, and at any predetermined pressure. In one embodiment the pressure of the oil delivered to the nozzle 26 is of the order of 1 10 psi. Also, merely by way of illustration, the capacity of the nozzle 26 can be 0.65 g.p.h. or 0.75 g.p.h., but dependent upon the furnace volume, but operation at other nozzle capacities can also be effected.

The nozzle body 23 has extending therealong a plurality of deeply cut air delivery grooves 27 for delivery of a suitable quantity of air therealong to aid in maintaining the desired temperature of the oil to the nozzle 26 and to provide air for the conversion to carbon monoxide ofcarbonaceous constituents of the fuel oil and for oxidation of any hydrogen which is released. The air supplied at this location can in some respects be considered as primary air.

The airbox 90 hasupper air tubes 41 extending upwardly and inwardly for supplying air for burnoff. V 7' The air box 94) also has a lower central air passageway 43 from which a target supporting and cooling air pipe 44 extends.

'The air box 90 also has an interior vertical end socket particularly to the drawings an A slightly downwardly in- 46 for the reception of an' insertable burnoff supply pipe 47.

The air box 90 also has ignition electrodes 48 carried thereby and extending through the walls 91 and 92.

Thehousing 16 preferably is composed of relatively thin sheet metal, hasa vertical wall with an opening 56 for the mounting in the housing 16 of the air box 99. The wall 55 has outwardly curved vertical side walls 5'7 extending therefrom. At the bottom of the wall 55 a rearwardly extending transverse brace 58, is connected thereto and has a baffle plate 59 secured thereto with the center in spaced relation for directing gases toward the center. The target supporting and cooling air pipe 44 extends through a mounting pipe or sleeve 44a carried by the airbox 90 above the baffle plate 59.

The target 17 preferably has two vertical wall sections concave in plan, extending from a central divider 69, the

is removably insertable into the sections 68 extending around to and meeting thewalls 57 in overlapped relation. The sections 68 and walls 57 are preferably adjustably connected, for target spacing from the nozzle 26, in any desired manner such as by rivets 71 carried by the sections 68 which extend through selected pairs of openings 72 in the walls 58 and are held by bendable tongues 73.

The target 17 at the rear thereof has a channel 75 se cured thereto into which a target support plate 76 which is welded to the upper end of the vertical terminal 77 of the target supporting and cooling air pipe 44.

The lower and upper ends of the rear portions of the target 17' have lower and upper bafiie plates 79 and 80 secured thereto to divert the gaseous material from the divider 69 and rear portions of the sections 68 within the confines of the sections 68 and walls 57. The bafiie plate 80 has a rear'downward inclined lip 81 to divert and distribute the air from the pipe #4.

Extending rearwardly along the top margin of the wall 57 a front upper horizontal baffle 100 is provided to which the walls 90, 91 and 92 are. secured in fluid tight relation. The bafiie 100 has pivoted thereto by pivots 94 horizontal rear side extensions liil which meet and rest upon the baffie 80. The bafiie 100 has a transverse upwardly extending rim 102 to support a'pendant colliinating baffie 103 having an upper flange 164' which hooks over the rim 102. The bailie 103 has a central openingltlS for the passage of fuel, air and gases therethrough and has side margins 166 to permit the gases to passback toward the air box at each side. The bafiie 103 also has a slot 107 to clear the pipe 44. V

The top portion of the wall 55 is held in place by the pipe 47 which extends down through a housing retainer cap and baflie 82 and the top wall of the air box 91) and into engagement with the socket 46. The pipe 47 socket 46 to retain the cap 82 and wall 55 in assembled positions. The side walls '57, battle 100, and brace 58 control the flow of the gases which are aspirated through the opening of the collimating bafi'le 103.

The burnoif assembly 19 includes the pipe 47 which extends upwardly at an inclination above the space enclosed within the sections 68 and walls 57, is closed at its upper end, has upwardly and outwardly directed openings .35 along the top thereof and has secured thereto a plurality of transverse tubes 86 with their interiors in communicationfwith the pipe 47 through openings 87. The ends of the tubes 86 are open for air discharge above the housing 16 and target 17.. i

The mode of operation. will now be pointed out;

The combustion area in the furnace 14 and the access doors and openings are assumed to be closed and airtight, except for communication with the stack. I

A clearance space between the inside of the furnace and the apparatus of the present invention of one inch or more isassumed to have been provided and a distance for stiffening and which serves between the adjacent wall of the furnace 14 and the vertical wall 55 of one to one and a half inches is also provided.

Oil is supplied through the oil supply pipe 49 to the nozzle body 23 and passes therethrough to the nozzle 26 where it is delivered in conical spray form preferably within an angle of 45 forwardly of the nozzle 26, and within the space within the confines of the housing 16 and target 17. The oil is preferably at a temperature at the nozzle 26 of about 160 to 180 F. This temperature is attained by a controlled heating action in the nozzle body 23.

Air from the fan or blower 11 is delivered under pressure into the air tube 10. The air from the air tubeli) can be considered as being separated into three kinds of streams, a quantity of air which passes along the grooves 27 and the interior of the sleeve 22a to prevent undue heating of the oil in the nozzle body 23 and for carbon monoxide generation which is delivered into the space enclosed within the housing 16 and target 17, a quantity of air which is delivered to and through the burnoff assembly 19 and tubes 41 which quantity is approximately equal to the air delivered to the other locations and a small quantity of cooling and combustion completing air which is delivered through the pipe 44 to the rear of the vertical target walls 68 and ultimately passes toward the upper part of the enclosure provided by the housing 16 and target 17. Air from the grooves 27 meets and intermingles with the atomized oil spray and within the high temperature reversed gases directed to and through the baflie ring 185 to efiect the complete vaporization of the fuel and movement through the central opening 105 toward the central divider 69 and target portions 67 is effected. The divider 69 and the curved shape of the target portions 67 effects a divided return flow along the vertical walls 68 and in part along the side walls 57 for redelivery through the central opening 105. The target portions 67 are of thin sheet metal so that they can quickly come up to their operating temperature which is about 1000 F.

The action which takes place within the enclosure in in the housing 16 and target 17 is the relatively slow conversion of the carbon in the fuel to carbon monoxide in an environment in which the quantity of air is such as to enhance such conversion but not the complete conversion to CO This subsequent burning to CO is effected to the location of the burnoif assembly 19, the baffie 160, the extensions 101, and the battle 80 providing boundaries of an opening smaller than the horizontal interior cross section of the housing 16 and target assembly 17.

The construction of the air box 90 of sheet metal avoids undesirable radiant heat effects at this location and other than to deliver heat to the nozzle body 23 for heating the oil delivered thereto. As indicated above the air passing along the grooves 27 prevents excessive heating.

Upon starting up, the combustion which occurs within and above the enclosure provided by housing 16 and target 17 will be a soft red flame which will persist for about 2 to 3 seconds and the flame will then gradually change to blue, as the temperature of the housing 16 and target 17 reach an equilibrium operating temperature.

To obtain optimum performance the burnoif assembly 19 can be swung about its mounting in the socket 46 to obtain a flame which is balanced or symmetrical. The lack of symmetry can arise from a number of causes including unbalance of the furnace contour, and burner positioning. Also, the spacing of the target portions 67 from the nozzle 26 can be varied by moving the rivets 71 to engage in other openings 72 in the side walls 57.

We claim:

1. Combustion apparatus comprising an air supply tube having an inner end for disposition within a furnace, an air delivery assembly in said end of said tube having a centrally located liquid fuel nozzle carried thereby, said nozzle having air delivery passageways formed therealong for limited delivery of air with the fuel, a housing and target assembly means of sheet metal having vertical enclosing wall portions surrounding a space into which the discharge path of said fuel nozzle is directed, the target portion of said assembly means having a central divider opposite said fuel nozzle, a pendant battle in said assembly means and within said space interposed between said nozzle and said target and having a delivery opening therethrough and side marginsspaced inwardly from the enclosing Wall portions for gas flow within said space from said target around said margins for recirculation through said opening, said air delivery assembly having a burnoff assembly means connected thereto and extending thereabove with air delivery outlets supplying air at a plurality of locations above said space.

2. Combustion apparatus as defined in claim 1 in which said air delivery assembly includes an air box at the end of said air tube, and said air box has a nozzle mounting member therethrough for holding said nozzle.

3. Combustion apparatus as defined in claim 2 in which said passageways formed along said nozzle are air delivery grooves for cooling said nozzle and for air delivery.

4. Combustion apparatus as defined in claim 2 in which said air box has burnoff air delivery tubes carried thereby.

5. Combustion apparatus as defined in claim 1 in which said air delivery assembly includes an air box in intersecting relation to said air tube, said air box has a vertical socket, and said burnotf assembly means has an air supply pipe mounted in said socket.

6. Combustion apparatus as defined in claim 1 in which said housing and target assembly means includes a housing portion supported on said air tube and a target portion having members adjustably connecting it to said housing portion for varying the horizontal distance between said fuel nozzle and said target portion.

7. Combustion apparatus as defined in claim 1 in which said housing and target assembly means includes a housing portion and a target portion said target portion having interiorly concave curved walls extending from said central divider outwardly and in meeting relation to said housing portion.

3. Combustion apparatus as defined in claim 1 in which said housing and target assembly means includes a target portion and a support for said target extends thereto from said air delivery assembly.

9. Combustion apparatus as defined in claim 8 in which said support is an air delivery tube for supplying cooling air to said target portion exteriorly thereof.

11]. Combustion apparatus as defined in claim 1 in which said air tube has an upper bracket plate thereon in supporting relation to said housing and target assembly means.

11. Combustion apparatus as defined in claim 1 in which said burnolf assembly means has an air supply ipe in detachable holding engagement with said housing and target assembly means.

12. Combustion apparatus comprising an air supply tube having an inner end for disposition within a furnace, an air delivery assembly having a body portion in intersecting relation at said end of said air supply tube, a tubular mounting member in said body portion, a liquid fuel nozzle carried by said mounting member, a housing and target assembly of sheet metal carried by said air tube having vertical housing wall portions and vertical target portions connected thereto and surrounding a space into which the discharge path of said nozzle is directed, said nozzle having grooves therealong for air delivery into said space, a vertical bafiie member in said space interposed between said nozzle and said target, said bafiie member having side margins spaced inwardly from said vertical wall portions for return flow of gas, and having a central opening for delivery of gas toward said target, and a burnoif assembly having an air supply pipe carried by said '5 body portion and communicating with said air tube, said burnoff assembly having a plurality of air delivery tubes extending upwardly with respect to said air delivery assembly with air delivery outlets supplying air to a plurality of spaced locations above said space.

13. Combustion apparatus as defined in claim 12 in which said target portion includes a central divider and interior-1y concaved Walls extending therefrom.

14. Combustion apparatus as defined in claim '12 in which a support for said target portion extends thereto from said body portion.

15. Combustion apparatus as defined in claim 12 in which said support is an air delivery tube for supplying cooling air to said target portion exteriorly thereof.

References Cited by the Examiner UNITED STATES PATENTS 2,164,225 6/39 Walker 158-4 2,329,272 9/43 Iorolerrion 158 4 2,660,230 11/53 Denker et a1. 158-4 2/54 Vignere 158-73 FOREIGN PATENTS V r 194 of1870 -Great Britain. 

1. COMBUSTION APPARATUS COMPRISING AN AIR SUPPLY TUBE HAVING AN INNER END FOR DISPOSITION WITHIN A FURNACE, AN AIR DELIVERY ASSEMBLY IN SAID END OF SAID TUBE HAVING A CENTRALLY LOCATED LIQUID FUEL NOZZLE CARRIED THEREBY, SAID NOZZLE HAVING AIR DELIVERY PASSAGEWAYS FORMED THEREALONG FOR LIMITED DELIVERY OF AIR WITH THE FUEL, A HOUSING AND TARGET ASSEMBLY MEANS OF SHEET METAL HAVING VERTICAL ENCLOSING WALL PORTIONS SURROUNDING A SPACE INTO WHICH THE DISCHARGE PATH OF SAID FUEL NOZZLE IS DIRECTED, THE TARGET PORTION OF SAID ASSEMBLY MEANS HAVING A CENTRAL DIVIDER OPPOSITE SAID FUEL NOZZLE, A PENDANT BAFFLE IN SAID ASSEMBLY MEANS AND WITHIN SAID SPACE INTERPOSED BETWEEN SAID NOZZLE AND SAID TARGET AND HAVING A DELIVERY OPENING THERETHROUGH AND SIDE MARGINS SPACED INWARDLY FROM THE ENCLOSING WALL PORTIONS FOR GAS FLOW WITHIN SAID SPACE FROM SAID TARGET AROUND SAID MARGINS FOR RECIRCULATION THROUGH SAID OPENING, SAID AIR DELIVERY ASSEMBLY HAVING A BURNOFF ASSEMBLY MEANS CONNECTED THERETO AND EXTENDING THEREABOVE WITH AIR DELIVERY OUTLETS SUPPLYING AIR AT A PLURALITY OF LOCATIONS ABOVE SAID SPACE. 